Electrode holder for searchlights



Aug. 18, 1936. F. R. HOUSE ELECTRODE HOLDER FOR SEARCHLIGHTS Origin a1 Filed June 25, 1935 INVENTOR 65 Fj'nNK R. H0 U5E Patented Aug. 18, 1936 UNETED STATES PATENT OFFICE ELECTRODE HOLDER FOR SEARCHLIGHTS Frank R. House, Baldwin Harbor, N. Y., assignor to Sperry Gyroscope Company, Inc., Brooklyn,

N. Y., a corporation of New York 4 Claims.

This invention relates to electrode holders for the carbons of high intensity searchlights or projector lamps, especially to the holder for the negative electrode.

The object of theinvention is to devise a negative'head or electrode holder which will stand up under the intense heat of the arc flames and which will remain in the operative position without attention for long periods. To accomplish this purpose, applicant has removed, as far as possible, all springs which are usually employed to hold the feed rollers on the electrode and the brushes against the electrode and utilizes a single spring for both purposes, placed remote from the arc and behind the negative electrode. Also, all feed roller shafts are made square with rounded corners, so that the pinions may be readily moved without driving out keys or pins. Such a shaft is also self-cleaning and will also scour dirt and grit out of the bearing.

A further improvement consists in the means provided for opening the brushes and feed rollers for recarboning, means being provided for lifting the feed rollers off the electrode before the current introducing brushes or jaws are removed.

This application constitutes a division of my pior application. now Patent #2,023,475 dated December 10, 1935, for Automatic feed for high intensity are lamps.

Referring to the drawing, showing the preferred form of my invention,

Fig. 1 is a side elevation of the negative electrode holder, showing a portion, also, of the positive holder.

Fig. 2 is a vertical section through the rotating axes of the negative feed gears and rollers.

Fig. 3 is a front view of the negative holder, partly in section.

Fig. 4 is an end view, on a larger scale, of one of the squared shafts on which the feed gears and pinions are mounted.

Referring to the drawing, I is the negative electrode holder for the negative electrode 2 of a high powered or high intensity lamp of the searchlight type, a portion of the positive holder being shown at 3 and the positive electrode tip at 4. The negative holder is usually secured to the upright (not shown) supporting the positive electrode holder by means of an arm 5. The upper portion of said arm forms the lower jaw 6 of a pair of jaws which guide the forward portion of the negative electrode and also introduce current to the same, the negative lead being connected to the arm 5. The upper jaw 1 is hinged on a pair of ears 8 and 8' projecting rearwardly from the arm 5, the upper jaw being provided with forked downward extensions 9 which are secured to a sleeve l0, which, in turn, is journaled in the ears 8 and 8. In the rear portion of the upper jaw l is also mounted a pair of pinions l I and I2, the former meshing with a pinion I3 on a squared shaft M rotatably mounted within the sleeve If]. The latter pinion l2 has a floating mounting, as hereinafter described. To the opposite end of shaft I4 is secured a bevel gear I 5 driven from a second bevel gear I6 on a feed shaft H to be rotated by suitable feeding mechanism (not shown) through a drive shaft I8 and a universal joint IS. The pinions ll and I2 are likewise provided with squared shafts 2D and 2!, on which are non-rotatably mounted feed rollers 22 and 23 which normally grip the negative electrode 2.

The upper jaw 1 may be raised to the dotted line position of Fig. 1 for recarboning., the current being led into the upper jaw through flexible leads 24 and 25. A single spring 26 situated away from the arc is utilized for holding both the feed rollers and current introducing jaws against the electrode and a single handle 21 is also made use of for releasing both the jaws and feed rollers for recarboning. The operating handle or lever is shown pivoted on the rear por tion of the hinged jaw 1 at 28 and the above mentioned elbow spring is shown as connected between a point 29 on said lever and a point 30 on the extension of arm 5 so as to hold the lower end of the lever upwardly and outwardly in the direction of the dotted line. A limit stop is provided by the top 3| of said lever contacting with the rear portion 9 of the jaw 1 to prevent binding of the gears in case an undersized carbon is used.

Also secured to said lever is a pair of arms 32, 32' in which the upper feed roller 22 is journaled, said roller lying within an oval opening or aperture 33 in the framework 9 which surrounds the feed roller. When the bottom of lever 21 is pressed inwardly, therefore, the first action is to lift the upper feed roller 22 out of contact with the electrode. Further movement of the lever brings the feed roller into contact with the upper part of the elliptical hole 33 so as to lift the entire jaw I about the sleeve H! as a pivot. The distances at, b. c, and d are so proportioned that a greater pressure is exerted on the feed rollers than on the clamping jaws 6 and i so that positive feeding action is assured even though the spring tension varies, because the pressure ratio remains fixed.

As stated above, each of the feed roller and feed pinion shafts near the electrode is preferably partially square, that is, provided with four flattened surfaces 35 and rounded corners 36. Such a shape will drive the pinions and feed rollers without keying or pinning so that they may be readily removed and, also, such a shaft rotates freely in an ordinary bearing. In fact, it is superior to a plain shaft since it is self-cleaning and will scour grit and dirt out of the bearing.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

Having described my invention what I claim and desire to secure by Letters Patent is:

1. In an electrode holder, a pair of gripping jaws, one pivoted on the other about an axis, a feed roller journaled in said other jaw, an operating lever pivoted on the pivoted jaw, a second feed roller journaled thereon and normally driven from the first roller, said rollers being nearer said pivotal axis than the point at which said jaws grip the electrode, and a common spring means for holding said jaws and feed rollers against the electrode, whereby a greater pressure is maintained by the rollers against the electrode than by the jaws, thereby assuring uninterrupted feeding.

2. In an electrode holder, a pair of gripping jaws, one pivoted on the other about an axis, a feed roller journaled in the fixed jaw, an operating lever pivoted on the pivoted jaw, a second feed roller journaled thereon and normally driven' from the first roller, spring means for holding said jaws and feed rollers against the electrode, and a lost motion connection between the second 5 mentioned roller and the pivoted jaw whereby said roller after being disengaged from the electrode by pressing on said lever engages the pivoted jaw and opens it also.

3. In an electrode holder, a pair of gripping jaws, one pivoted on the other about an axis, a feed roller journalled in the fixed jaw, a gear shaft for driving said roller journaled about said axis, an operating lever pivoted on the pivoted jaw, a second feed roller journaled thereon and normally driven from the first roller, spring means acting on said lever for holding said jaws and feed rollers against the electrode, and a lost motion connection between the second mentioned roller and the pivoted jaw whereby said roller after being 20 disengaged from the electrode by pressing on said lever, engages the pivoted jaw and opens it also.

4. In an electrode holder,a pair of gripping jaws, one pivoted on the other about an axis, a feed 25 roller journaled in the fixed jaw, an operating lever pivoted on the pivoted jaw, a second feed roller journaled thereon and normally driven from the first roller, and a hairpin spring connecting said lever and holder and positioned away from the are for holding both the feed rollers and the gripping jaws on the electrode, said jaws being adjacent the arc and adapted to introduce current to the electrode.

FRANK R. HOUSE. 

